With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploratio...With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploration of coal fields. First, we introduce principles and features of three kinds of inversion methods. i.e., Model-Based Inversion, Constrained Sparse Spike Inversion (CSSI) and Geology-Seismic Feature Inversion. Secondly, these inversion methods are contrasted in their application to 3D seismic data from some coalfields in western China. The main information provided by the research includes: improving the vertical resolution of coal deposit strata, inferring lateral variation of the lithology and predicting coal seams and their roof lithology. Finally, the comparison between the three methods shows that the model-based inversion has the higher resolution, while CSSI inversion has better waveform continuity. The geology-seismic feature inversion requires information from a large number of wells and many types of logging curves of good quality. All three methods can meet the requirements of seismic exploration for lithological exploration in coal fields.展开更多
Walkaway VSP technology is commonly seen in the seismic development stage in the middle and late stages of the oilfield.Its advantage over conventional zero-offset VSP and non-zero well-source distance VSP is mainly d...Walkaway VSP technology is commonly seen in the seismic development stage in the middle and late stages of the oilfield.Its advantage over conventional zero-offset VSP and non-zero well-source distance VSP is mainly due to the higher coverage of the Walkaway VSP acquisition process and the larger acquisition range.The resolution and signal-to-noise ratio are higher.Walkaway VSP technology has a very good application effect on solving complex structural problems and thin interbed reservoir problems.This paper mainly introduces a VSP constrained sparse spike inversion method based on high-precision VSP data.For the data acquired by the eight-azimuth Walkaway VSP in a work area of Bohai Gulf,a new method of 3D seismic-VSP joint seismic inversion is established.In the application of the actual work area,good inversion results based on Walkaway VSP data were obtained,and a new R24 small layer above the top boundary of the NmRIll oil group was depicted.This result meets the needs of development seismic technology and is used to solve thin interbed reservoirs exploration problems that have very important practical significance.展开更多
B and C sands of the Lower Goru Formation of Cretaceous are proven reservoirs in different parts of the Middle and Lower Indus Basin,Pakistan.Most of the discoveries in this basin have been made in structural traps.Ho...B and C sands of the Lower Goru Formation of Cretaceous are proven reservoirs in different parts of the Middle and Lower Indus Basin,Pakistan.Most of the discoveries in this basin have been made in structural traps.However,in Sawan gas field;structural inversion,deep burial depth and heterogeneity of reservoir intervals make it difficult to demarcate the sweetness zones through conventional seismic analysis.In this work,different data sets have been integrated through constrained sparse spike inversion to mark sweetness zones in B and C sands of this formation.C sand contains four sweetness zones;the main sweetness zone is located towards the east while three subtle sweetness zones were identified towards the west of Sawan fault.The location of producing and nonproducing wells within the sweetness and outside of sweetness zones confirms the credibility of this work.B sand includes three sweetness zones located towards the west of Sawan fault.Moreover,inverted porosity results not only show good agreement with the porosity log of blind well(Sawan-02)but also show good matching with the core porosities.Hence integration of different data sets leads to demarcate the accurate location,size and extent of the sweetness zones.展开更多
基金part of an ongoing project of the National Important Industry Technological Development Project (High Precision 3D Seismic Technology of Coal Resources of Western China)the financial support from the National Basic Research Program of China (No.2009CB 219603)the National Key Scientific and Technological Project of China (No.2008ZX05035-005-003HZ)
文摘With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploration of coal fields. First, we introduce principles and features of three kinds of inversion methods. i.e., Model-Based Inversion, Constrained Sparse Spike Inversion (CSSI) and Geology-Seismic Feature Inversion. Secondly, these inversion methods are contrasted in their application to 3D seismic data from some coalfields in western China. The main information provided by the research includes: improving the vertical resolution of coal deposit strata, inferring lateral variation of the lithology and predicting coal seams and their roof lithology. Finally, the comparison between the three methods shows that the model-based inversion has the higher resolution, while CSSI inversion has better waveform continuity. The geology-seismic feature inversion requires information from a large number of wells and many types of logging curves of good quality. All three methods can meet the requirements of seismic exploration for lithological exploration in coal fields.
基金supported by the Natural Science Foundation of China(41974124)the China Scholarship Council(201906440068).
文摘Walkaway VSP technology is commonly seen in the seismic development stage in the middle and late stages of the oilfield.Its advantage over conventional zero-offset VSP and non-zero well-source distance VSP is mainly due to the higher coverage of the Walkaway VSP acquisition process and the larger acquisition range.The resolution and signal-to-noise ratio are higher.Walkaway VSP technology has a very good application effect on solving complex structural problems and thin interbed reservoir problems.This paper mainly introduces a VSP constrained sparse spike inversion method based on high-precision VSP data.For the data acquired by the eight-azimuth Walkaway VSP in a work area of Bohai Gulf,a new method of 3D seismic-VSP joint seismic inversion is established.In the application of the actual work area,good inversion results based on Walkaway VSP data were obtained,and a new R24 small layer above the top boundary of the NmRIll oil group was depicted.This result meets the needs of development seismic technology and is used to solve thin interbed reservoirs exploration problems that have very important practical significance.
文摘B and C sands of the Lower Goru Formation of Cretaceous are proven reservoirs in different parts of the Middle and Lower Indus Basin,Pakistan.Most of the discoveries in this basin have been made in structural traps.However,in Sawan gas field;structural inversion,deep burial depth and heterogeneity of reservoir intervals make it difficult to demarcate the sweetness zones through conventional seismic analysis.In this work,different data sets have been integrated through constrained sparse spike inversion to mark sweetness zones in B and C sands of this formation.C sand contains four sweetness zones;the main sweetness zone is located towards the east while three subtle sweetness zones were identified towards the west of Sawan fault.The location of producing and nonproducing wells within the sweetness and outside of sweetness zones confirms the credibility of this work.B sand includes three sweetness zones located towards the west of Sawan fault.Moreover,inverted porosity results not only show good agreement with the porosity log of blind well(Sawan-02)but also show good matching with the core porosities.Hence integration of different data sets leads to demarcate the accurate location,size and extent of the sweetness zones.
